Ive purchased Alli in the store AND on ebay (from trusted sellers ONLY) and have lost 35 pounds, with a slight change in my diet.  My dr advised me that the Rx strength Orlistat is 120mg, so you can actually take two tablets at a time.  Ive lost that much weight and managed to keep it off. Just purchased another big bottle and hoping to go for another 35 in 6 more months!